Toy building set element



FIG. 1 is a top perspective view of the toy building set element design;

FIG. 2 is a side perspective view thereof;

FIG. 3 is an end view hereof, the opposite end being identical;

FIG. 4 is a top plan view thereof, the bottom being identical; and,

FIG. 5 is a front elevational view thereof, the rear being identical. 

The ornamental design for a toy building set element, as shown and described. 